Nucleation and growth in solution synthesis of nanostructures – From fundamentals to advanced applications

Nucleation and growth are two important and entwined processes in materials synthesis and engineering. While understanding of the fundamental mechanisms of the processes remain challenging, there is a growing demand for much improved control over and modification of nanostructures with precise geometrical and chemical features, well-tailored surface properties and functional attributes. To this end, we first examine the key concepts of the classical and non-classical theories and then emphasise mechanistic studies of nucleation and growth. Particularly, the state-of-the-art imaging, signal and/or data acquisition techniques are discussed, including in-situ liquid phase transmission electron microscopy, in-situ synchrotron X-ray diffraction, microfluidic platforms and machine learning. Both quantitative and qualitative experimental results with high temporal and spatial resolutions provide further insights into these nanofabrication processes for representative systems, such as Au nanoparticles and CaCO3, and subsequently guide the rational design and production of materials with desirable properties. Based on current knowledge, strategies of leveraging external fields to manipulate the nucleation and growth processes are presented. Several case studies in important technological scenarios are discussed to inspire further attempts for precisely engineered solutions. Finally, further understanding of the processes are highlighted along with potential applications and future perspectives of controlling solution-synthesized nanostructures.